Systems and methods for multimedia signal processing and transmission

ABSTRACT

A method for processing and transmitting multimedia signals received from a plurality of channels are provided. The method may include receiving at least two multimedia signals from a plurality of channels, and generating a composite multimedia digital signal by coding the multimedia signals in a frame format. At least one of the multimedia signals may include a video signal. The frame format may include an active zone and a blanking zone, the active zone may be configured to encode at least part of the multimedia signals, and the blanking zone may be configured to encode format information. The method may further include converting at least part of the encoded multimedia signals in the active zone into analog signals to generate a composite multimedia signal. The method may further include transmitting the composite multimedia signal to a receiving device via a transmission medium.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International ApplicationPCT/CN2018/111362, filed on Oct. 23, 2018, which claims priority ofChinese Patent Application No. 201710992714.9 filed on Oct. 23, 2017,the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure generally relates to systems and methods forprocessing multimedia signals, and in particular, to systems and methodsfor processing and transmitting multimedia signals received from aplurality of channels.

BACKGROUND

Multimedia technology has been widely used in various fields in recentyears, such as computer industry, entertainment, and video monitoring. Achallenge in multimedia technology is the processing and transmission ofmultimedia signals received from a plurality of channels. Normally, aplurality of transmission medium (e.g., a plurality of cables) is neededto transmit the multimedia signals received from the plurality ofchannels, which may cause a waste of transmission resources.Accordingly, it is desirable to provide systems and methods forprocessing and transmitting multimedia signals received from a pluralityof channels more efficiently, thus saving the transmission cost.

SUMMARY

In one aspect of the present disclosure, a method for processing andtransmitting multimedia signals received from a plurality of channels isprovided. The method may be implemented on a computing device which hasat least one processor and at least one computer-readable storagemedium. The method may include one or more of the following operations.At least two multimedia signals may be received from a plurality ofchannels. At least one of the at least two multimedia signals mayinclude a video signal. A composite multimedia digital signal may begenerated by coding the at least two multimedia signals in a frameformat. The frame format may include an active zone and a blanking zone,the active zone may be configured to encode at least part of the atleast two multimedia signals, and the blanking zone may be configured toencode format information. At least part of the encoded multimediasignals in the active zone may be converted into analog signals togenerate a composite multimedia signal. The composite multimedia signalmay be transmitted to a receiving device via a transmission medium.

In some embodiments, the active zone may be configured to encode thevideo signal, and the converting the at least part of the at least twomultimedia signals in the active zone into analog signals may includeconverting the video signal in the active zone into analog signals.

In some embodiments, the active zone of the frame format may include aplurality of active lines configured to encode the video signal, and ahorizontal blanking zone between at least one pair of adjacent activelines of the plurality of active lines. The horizontal blanking mayinclude a horizontal synchronization signal.

In some embodiments, each of the at least two multimedia signals mayinclude a video signal, and the format information may indicate acombination form of the video signals in the plurality of active linesin the active zone.

In some embodiments, the generating the composite multimedia digitalsignal by coding the at least two multimedia signals in the frame formatmay include one or more of the following operations. The video signalsmay be encoded into the plurality of active lines according to theformat information. A separator may be inserted between at least onepair of adjacent video signals in at least one of the plurality ofactive lines.

In some embodiments, the horizontal synchronization signal and theseparator may have different time widths.

In some embodiments, the active zone may include a horizontal blankingzone corresponding to each of the plurality of active lines. Each of theat least two multimedia signals may include an audio signal. Thegenerating the composite multimedia digital signal may include one ormore of the following operations. For each of the plurality of activelines in the active zone, a combination of the audio signals may bedetermined according to the combination form of the video signals in theactive line. For each of the plurality of active lines in the activezone, the combination of the audio signals may be encoded into thehorizontal blanking zone corresponding to the active line.

In some embodiments, at least one of the at least two multimedia signalsmay include an audio signal, and the generating the composite multimediadigital signal may include encoding the audio signal into the horizontalblanking zone.

In some embodiments, the size of the blanking zone of the frame formatmay be smaller than 10 bytes.

In some embodiments, the transmission medium may be a coaxial cable.

In some embodiments, the method may further include converting theanalog signals of the composite multimedia signal into digital signals.

In some embodiments, each of the at least two multimedia signals mayinclude at least one of a horizontal synchronization signal or a framesynchronization signal, and the generating the composite multimediadigital signal by coding the at least two multimedia signals may includeone or more of the following operations. The at least one of thehorizontal synchronization signal or the frame synchronization signal ineach multimedia signal may be detected. Valid data from the at least twomultimedia signals may be extracted based on the detected at least oneof the horizontal synchronization signal or the frame synchronizationsignal in each multimedia signal. The composite multimedia digitalsignal may be generated by coding the valid data.

In yet another aspect of the present disclosure, a method for processingand transmitting multimedia signals received from a plurality ofchannels is provided. The method may be implemented on a computingdevice which has at least one processor and at least onecomputer-readable storage medium. The method may include one or more ofthe following operations. A composite multimedia signal in a frameformat may be received. The composite multimedia signal may be generatedbased on at least two multimedia signals that are received from aplurality of channels. The at least one of the at least two multimediasignals may include a video signal. The frame format may include anactive zone and a blanking zone, the active zone may be configured toencode analog signals converted from at least part of the at least twomultimedia signals, and the blanking zone may be configured to encodeformat information. The composite multimedia signal may be demodulatedaccording to the format information. The demodulated compositemultimedia signal may be transmitted to one or more output devices. Thedemodulating the composite multimedia signal according to the formatinformation may include converting the analog signals in the active zoneinto digital signals.

In some embodiments, the transmitting the demodulated compositemultimedia digital signal to one or more output devices may include oneor more of the following operations. The at least two multimedia signalsmay be determined from the demodulated composite multimedia digitalsignal. Each of the at least two multimedia signals may be transmittedto a distinctive output device.

In yet another aspect of the present disclosure, a system for processingand transmitting multimedia signals received from a plurality ofchannels is provided. The system may include a storage device storing aset of instructions, and at least one processor in communication withthe storage device. When executing the set of instructions, the at leastone processor may be configured to cause the system to execute one ormore of the following operations. At least two multimedia signals may bereceived from a plurality of channels. At least one of the at least twomultimedia signals may include a video signal. A composite multimediadigital signal may be generated by coding the at least two multimediasignals in a frame format. The frame format may include an active zoneand a blanking zone, the active zone may be configured to encode atleast part of the at least two multimedia signals, and the blanking zonemay be configured to encode format information. At least part of theencoded multimedia signals in the active zone may be converted intoanalog signals to generate a composite multimedia signal. The compositemultimedia signal may be transmitted to a receiving device via atransmission medium.

In yet another aspect of the present disclosure, a system for processingand transmitting multimedia signals received from a plurality ofchannels is provided. The system may include a storage device storing aset of instructions, and at least one processor in communication withthe storage device. When executing the set of instructions, the at leastone processor may be configured to cause the system to execute one ormore of the following operations. A composite multimedia signal in aframe format may be received. The composite multimedia signal may begenerated based on at least two multimedia signals that are receivedfrom a plurality of channels. The at least one of the at least twomultimedia signals may include a video signal. The frame format mayinclude an active zone and a blanking zone, the active zone may beconfigured to encode analog signals converted from at least part of theat least two multimedia signals, and the blanking zone may be configuredto encode format information. The composite multimedia signal may bedemodulated according to the format information. The demodulatedcomposite multimedia signal may be transmitted to one or more outputdevices. The demodulating the composite multimedia signal according tothe format information may include converting the analog signals in theactive zone into digital signals.

In yet another aspect of the present disclosure, a non-transitorycomputer readable medium is provided. The non-transitory computerreadable medium storing instructions, the instructions, when executed byat least one processor of a system, may cause the system to implement amethod. The method may include one or more of the following operations.At least two multimedia signals may be received from a plurality ofchannels. At least one of the at least two multimedia signals mayinclude a video signal. A composite multimedia digital signal may begenerated by coding the at least two multimedia signals in a frameformat. The frame format may include an active zone and a blanking zone,the active zone may be configured to encode at least part of the atleast two multimedia signals, and the blanking zone may be configured toencode format information. At least part of the encoded multimediasignals in the active zone may be converted into analog signals togenerate a composite multimedia signal. The composite multimedia signalmay be transmitted to a receiving device via a transmission medium.

In yet another aspect of the present disclosure, a non-transitorycomputer readable medium is provided. The non-transitory computerreadable medium storing instructions, the instructions, when executed byat least one processor of a system, may cause the system to implement amethod. The method may include one or more of the following operations.A composite multimedia signal in a frame format may be received. Thecomposite multimedia signal may be generated based on at least twomultimedia signals that are received from a plurality of channels. Theat least one of the at least two multimedia signals may include a videosignal. The frame format may include an active zone and a blanking zone,the active zone may be configured to encode analog signals convertedfrom at least part of the at least two multimedia signals, and theblanking zone may be configured to encode format information. Thecomposite multimedia signal may be demodulated according to the formatinformation. The demodulated composite multimedia signal may betransmitted to one or more output devices. The demodulating thecomposite multimedia signal according to the format information mayinclude converting the analog signals in the active zone into digitalsignals.

Additional features will be set forth in part in the description whichfollows, and in part will become apparent to those skilled in the artupon examination of the following and the accompanying drawings or maybe learned by production or operation of the examples. The features ofthe present disclosure may be realized and attained by practice or useof various aspects of the methodologies, instrumentalities andcombinations set forth in the detailed examples discussed below.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is further described in terms of exemplaryembodiments. These exemplary embodiments are described in detail withreference to the drawings. These embodiments are non-limiting exemplaryembodiments, in which like reference numerals represent similarstructures throughout the several views of the drawings, and wherein:

FIG. 1 is a schematic diagram illustrating an exemplary multimediasystem according to some embodiments of the present disclosure;

FIG. 2 is a schematic diagram illustrating exemplary hardware and/orsoftware components of a computing device according to some embodimentsof the present disclosure;

FIG. 3 is a block diagram illustrating an exemplary processing engineaccording to some embodiments of the present disclosure;

FIG. 4A is a flowchart illustrating an exemplary process for generatingand transmitting a composite multimedia signal according to someembodiments of the present disclosure;

FIG. 4B is a schematic diagram illustrating an exemplary frame format ofa frame of a composite multimedia digital signal according to someembodiments of the present disclosure;

FIG. 5 is a block diagram illustrating an exemplary receiving deviceaccording to some embodiments of the present disclosure;

FIG. 6 is a flowchart illustrating an exemplary process for processing acomposite multimedia signal according to some embodiments of the presentdisclosure;

FIGS. 7 and 8 are schematic diagrams illustrating exemplary traditionalways of transmitting video signals;

FIGS. 9 and 10 are schematic diagrams illustrating exemplary ways oftransmitting video signals according to some embodiments of the presentdisclosure; and

FIG. 11 is a schematic diagram illustrating an exemplary process ofgenerating a composite video signal according to some embodiments of thepresent disclosure.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth by way of examples in order to provide a thorough understanding ofthe relevant disclosure. However, it should be apparent to those skilledin the art that the present disclosure may be practiced without suchdetails. In other instances, well-known methods, procedures, systems,components, and/or circuitry have been described at a relativelyhigh-level, without detail, in order to avoid unnecessarily obscuringaspects of the present disclosure. Various modifications to thedisclosed embodiments will be readily apparent to those skilled in theart, and the general principles defined herein may be applied to otherembodiments and applications without departing from the spirit and scopeof the present disclosure. Thus, the present disclosure is not limitedto the embodiments shown, but to be accorded the widest scope consistentwith the claims.

It will be understood that the term “system,” “engine,” “unit,”“module,” and/or “block” used herein are one method to distinguishdifferent components, elements, parts, section or assembly of differentlevel in ascending order. However, the terms may be displaced by otherexpression if they may achieve the same purpose.

Generally, the word “module,” “unit,” or “block,” as used herein, refersto logic embodied in hardware or firmware, or to a collection ofsoftware instructions. A module, a unit, or a block described herein maybe implemented as software and/or hardware and may be stored in any typeof non-transitory computer-readable medium or other storage device. Insome embodiments, a software module/unit/block may be compiled andlinked into an executable program. It will be appreciated that softwaremodules can be callable from other modules/units/blocks or fromthemselves, and/or may be invoked in response to detected events orinterrupts. Software modules/units/blocks configured for execution oncomputing devices (e.g., processor 210 as illustrated in FIG. 2) may beprovided on a computer readable medium, such as a compact disc, adigital video disc, a flash drive, a magnetic disc, or any othertangible medium, or as a digital download (and can be originally storedin a compressed or installable format that needs installation,decompression, or decryption prior to execution). Such software code maybe stored, partially or fully, on a storage device of the executingcomputing device, for execution by the computing device. Softwareinstructions may be embedded in firmware, such as an EPROM. It will befurther appreciated that hardware modules (or units or blocks) may beincluded in connected logic components, such as gates and flip-flops,and/or can be included in programmable units, such as programmable gatearrays or processors. The modules (or units or blocks) or computingdevice functionality described herein may be implemented as softwaremodules (or units or blocks), but may be represented in hardware orfirmware. In general, the modules (or units or blocks) described hereinrefer to logical modules (or units or blocks) that may be combined withother modules (or units or blocks) or divided into sub-modules (orsub-units or sub-blocks) despite their physical organization or storage.

It will be understood that when a unit, engine, module, or block isreferred to as being “on,” “connected to,” or “coupled to” another unit,engine, module, or block, it may be directly on, connected or coupledto, or communicate with the other unit, engine, module, or block, or anintervening unit, engine, module, or block may be present, unless thecontext clearly indicates otherwise. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

The terminology used herein is for the purposes of describing particularexamples and embodiments only and is not intended to be limiting. Asused herein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “include” and/or“comprise,” when used in this disclosure, specify the presence ofintegers, devices, behaviors, stated features, steps, elements,operations, and/or components, but do not exclude the presence oraddition of one or more other integers, devices, behaviors, features,steps, elements, operations, components, and/or groups thereof.

The term “multimedia” may refer to a means or tool for storing anddelivering information that uses one content form or a combination ofdifferent content forms, such as but not limited to text, an audio, animage, an animation, a video, an interactive content, or the like, orany combination thereof. The term “multimedia signal” may refer to asignal in any signal form (e.g., a digital signal, an analog signal, acombination of digital signal and analog signal) that encodes multimediacontent. The term “composite multimedia digital signal” may refer to adigital signal that combines two or more multimedia signals. The term“composite multimedia signal” may refer to an analog signal or a mixedsignal of digital signals and analog signals that combines two or moremultimedia signals.

An aspect of the present disclosure relates to systems and methods forprocessing and transmitting a plurality of multimedia signals receivedfrom a plurality of channels. The systems and methods may generate acomposite multimedia digital signal by coding the multimedia signals ina frame format. The frame format may include an active zone configuredto encode at least part of the multimedia signals and a blanking zoneconfigured to encode format information. The systems and methods maycovert at least a portion of the encoded multimedia signals in theactive zone into analog signals to generate a composite multimediasignal. Compared with the original multimedia signals which may betransmitted via a plurality of transmission medium, the compositemultimedia signal may be transmitted via a single transmission medium.In addition, the composite multimedia signal, as a mixed signal ofdigital signals and analog signals, may be more suitable forlong-distance transmission than the composite multimedia digital signal.As such, the multimedia signals may be transmitted in a more efficientand economic manner.

FIG. 1 illustrates a schematic diagram of an exemplary multimedia system100 according to some embodiments of the present disclosure. As shown,the multimedia system 100 may include a server 110, a storage device120, an acquisition device 130, an output device 140, and a network 150.

The server 110 may process information and/or data relating to themultimedia system 100 to perform one or more functions described in thepresent disclosure. In some embodiments, the server 110 may include oneor more processing engines 112 (e.g., single-core processing engine(s)or multi-core processor(s)). Merely by way of example, the processingengine 112 may include a central processing unit (CPU), anapplication-specific integrated circuit (ASIC), an application-specificinstruction-set processor (ASIP), a graphics processing unit (GPU), aphysics processing unit (PPU), a digital signal processor (DSP), a fieldprogrammable gate array (FPGA), a programmable logic device (PLD), acontroller, a microcontroller unit, a reduced instruction-set computer(RISC), a microprocessor, or the like, or any combination thereof.

The server 110 may be a single server or a server group. The servergroup may be centralized, or distributed (e.g., server 110 may be adistributed system). In some embodiments, the server 110 may be local orremote. For example, the server 110 may access information and/or datastored in the acquisition device 130, and/or the storage device 120 viathe network 150. As another example, the server 110 may be directlyconnected to the acquisition device 130, and/or the storage device 120to access stored information and/or data. In some embodiments, theserver 110 may be implemented on a cloud platform. Merely by way ofexample, the cloud platform may include a private cloud, a public cloud,a hybrid cloud, a community cloud, a distributed cloud, an inter-cloud,a multi-cloud, or the like, or any combination thereof. In someembodiments, the server 110 may be implemented on a computing device 200having one or more components illustrated in FIG. 2 of the presentdisclosure.

The storage device 120 may store data and/or instructions. The dataand/or instructions may be obtained from, for example, the server 110,the acquisition device 130, and/or any other component of the multimediasystem 100.

In some embodiments, the storage device 120 may store data and/orinstructions that the server 110 may execute or use to perform exemplarymethods described in the present disclosure. For example, the storagedevice 120 may store multimedia signals acquired by one or moreacquisition devices 130. As another example, the storage device 120 maystore a composite multimedia (digital) signal generated based on themultimedia signals. In some embodiments, the storage device 120 mayinclude a mass storage, a removable storage, a volatile read-and-writememory, a read-only memory (ROM), or the like, or any combinationthereof. Exemplary mass storage may include a magnetic disk, an opticaldisk, a solid-state drives, etc. Exemplary removable storage may includea flash drive, a floppy disk, an optical disk, a memory card, a zipdisk, a magnetic tape, etc. Exemplary volatile read-and-write memory mayinclude a random access memory (RAM). Exemplary RAM may include adynamic RAM (DRAM), a double date rate synchronous dynamic RAM (DDRSDRAM), a static RAM (SRAM), a thyristor RAM (T-RAM), and azero-capacitor RAM (Z-RAM), etc. Exemplary ROM may include a mask ROM(MROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM),an electrically erasable programmable ROM (EEPROM), a compact disk ROM(CD-ROM), and a digital versatile disk ROM, etc. In some embodiments,the storage device 120 may be implemented on a cloud platform. Merely byway of example, the cloud platform may include a private cloud, a publiccloud, a hybrid cloud, a community cloud, a distributed cloud, aninter-cloud, a multi-cloud, or the like, or any combination thereof.

In some embodiments, the storage device 120 may be connected to thenetwork 150 to communicate with one or more components of the multimediasystem 100 (e.g., the server 110, the acquisition device 130). One ormore components of the multimedia system 100 may access the data orinstructions stored in the storage device 120 via the network 150. Insome embodiments, the storage device 120 may be directly connected to orcommunicate with one or more components of the multimedia system 100(e.g., the server 110, the acquisition device 130). In some embodiments,the storage device 120 may be part of another component of themultimedia system 100, such as the server 110, the acquisition device130, or the output device 140.

In some embodiments, one or more components of the multimedia system 100(e.g., the server 110, the acquisition device 130) may have a permissionto access the storage device 120. For example, the server 110 or theacquisition device 130 may read and/or modify the format of a compositemultimedia digital signal stored in the storage device 120.

The acquisition device 130 may be and/or include any suitable devicethat is capable of acquiring a multimedia signal. Exemplary acquisitiondevices may include a camera (e.g., a digital camera, an analog camera,an IP camera (IPC)), a video recorder, a scanner, a mobile phone, atablet computing device, a wearable computing device, a monitoringequipment, an infrared imaging device (e.g., a thermal imaging device),a microphone, or the like. In some embodiments, the acquisition device130 may include a mobile phone 130-1, a computer 130-2, a surveillancecamera 130-3, a microphone 130-4, etc. The computer 130-2 may includebut not limit to a laptop, a tablet computer, a desktop, or the like, orany combination thereof. The surveillance camera 130-3 may include butnot limit to a gun camera, a dome camera, an integrated camera, amonocular camera, a binocular camera, a multi-view camera, or the like,or any combination thereof. The multimedia signal acquired by theacquisition device 130 may include a video signal, an audio signal, animage signal, a text signal, an animation signal, or the like, or anycombination thereof. In some embodiments, the acquisition device 130 mayinclude a plurality of components each of which can acquire a multimediasignal. For example, the acquisition device 130 may include a pluralityof sub-cameras that can take pictures or videos simultaneously. Asanother example, the acquisition device 130 may include a camera and amicrophone.

The output device 140 may be and/or include any suitable device that candisplay or output information in a human-readable form, such as text,image, audio, video, graph, animation, or the like, or any combinationthereof. Exemplary output devices may include a mobile device 140-1, acomputer 140-2, a display device 140-3, a loudspeaker 140-4, a headset,a microphone, a music player, an e-book reader, a printer, a projector,or the like, or a combination thereof. The mobile device 140-1 mayinclude a mobile phone, a personal digital assistant (PDA), or the like.The computer 140-2 may include a laptop, a tablet computer, a desktop,or the like. The display device 140-3 may include a cathode ray tube(CRT) display, a liquid crystal display (LCD), a light emitting diode(LED) display, a plasma display panel (PDP), a 3D display, or the like.In some embodiments, the output device 140 may be connected to one ormore components of the multimedia system 100 (e.g., the server 110, thestorage device 120, the acquisition device 130) via the network 150,such as a wireless network or a wired network (e.g., a coaxial cablenetwork).

The network 150 may include any suitable network that can facilitateexchange of information and/or data for the multimedia system 100. Insome embodiments, one or more components in the multimedia system 100(e.g., the server 110, the storage device 120, and the acquisitiondevice 130) may send information and/or data to another component(s) inthe multimedia system 100 via the network 150. For example, the server110 may obtain/acquire multimedia signals from the acquisition device130 via the network 150. In some embodiments, the network 150 may be anytype of wired or wireless network, or combination thereof. Merely by wayof example, the network 150 may include a cable network (e.g., a coaxialcable network), a wireline network, an optical fiber network, atelecommunications network, an intranet, an Internet, a local areanetwork (LAN), a wide area network (WAN), a wireless local area network(WLAN), a metropolitan area network (MAN), a wide area network (WAN), apublic telephone switched network (PSTN), a Bluetooth network, a ZigBeenetwork, a near field communication (NFC) network, or the like, or anycombination thereof.

In some embodiments, the multimedia system 100 may include a receivingdevice (not shown in the FIG. 1). The receiving device may receiveinformation and/or signals from one or more components in the multimediasystem 100 (e.g., the server 110, the acquisition device 130) via thenetwork 150. The receiving device may further process the informationand/or signals and transmit the processed information and/or signals tothe output device for display. Merely by way of example, the receivingdevice may receive a composite multimedia signal from, for example, theserver 110. The receiving device may demodulate the composite multimediasignal, and transmit the demodulated composite multimedia signal to oneor more output devices 140 for display. In some embodiments, thereceiving device may be part of the server 110 or the output device 140.Details regarding the receiving device may be found elsewhere in thepresent disclosure (e.g., FIGS. 5 and 6 and the relevant descriptionsthereof).

It should be noted that the above description is merely provided for thepurposes of illustration, and not intended to limit the scope of thepresent disclosure. For persons having ordinary skills in the art,multiple variations and modifications may be made under the teachings ofthe present disclosure. For example, the multimedia system 100 mayinclude one or more terminals (e.g., a console) configured to receive auser input. As another example, the processing engine 112 may beintegrated into the acquisition device 130. However, those variationsand modifications do not depart from the scope of the presentdisclosure.

FIG. 2 is a schematic diagram illustrating exemplary hardware and/orsoftware components of an exemplary computing device 200 on which theprocessing engine 112, the receiving device, and/or the output device140 may be implemented according to some embodiments of the presentdisclosure. As illustrated in FIG. 2, the computing device 200 mayinclude a processor 210, a storage 220, an input/output (I/O) 230, and acommunication port 240.

The processor 210 may execute computer instructions (e.g., program code)and perform functions of the processing engine 112 in accordance withtechniques described herein. The computer instructions may include, forexample, routines, programs, objects, components, data structures,procedures, modules, and functions, which perform particular functionsdescribed herein. For example, the processor 210 may process multimediasignals obtained from the acquisition device 130, the storage device120, and/or any other component of the multimedia system 100. In someembodiments, the processor 210 may include one or more hardwareprocessors, such as a microcontroller, a microprocessor, a reducedinstruction set computer (RISC), an application specific integratedcircuits (ASICs), an application-specific instruction-set processor(ASIP), a central processing unit (CPU), a graphics processing unit(GPU), a physics processing unit (PPU), a microcontroller unit, adigital signal processor (DSP), a field programmable gate array (FPGA),an advanced RISC machine (ARM), a programmable logic device (PLD), anycircuit or processor capable of executing one or more functions, or thelike, or any combinations thereof.

Merely for illustration, only one processor is described in thecomputing device 200. However, it should be noted that the computingdevice 200 in the present disclosure may also include multipleprocessors, thus operations and/or method steps that are performed byone processor as described in the present disclosure may also be jointlyor separately performed by the multiple processors. For example, if inthe present disclosure the processor of the computing device 200executes both step A and step B, it should be understood that step A andstep B may also be performed by two or more different processors jointlyor separately in the computing device 200 (e.g., a first processorexecutes step A and a second processor executes step B, or the first andsecond processors jointly execute steps A and B).

The storage 220 may store data/information obtained from the server 110,the acquisition device 130, the storage device 120, and/or any othercomponent of the multimedia system 100. In some embodiments, the storage220 may include a mass storage, a removable storage, a volatileread-and-write memory, a read-only memory (ROM), or the like, or anycombination thereof. For example, the mass storage may include amagnetic disk, an optical disk, a solid-state drive, etc. The removablestorage may include a flash drive, a floppy disk, an optical disk, amemory card, a zip disk, a magnetic tape, etc. The volatileread-and-write memory may include a random access memory (RAM). The RAMmay include a dynamic RAM (DRAM), a double date rate synchronous dynamicRAM (DDR SDRAM), a static RAM (SRAM), a thyristor RAM (T-RAM), and azero-capacitor RAM (Z-RAM), etc. The ROM may include a mask ROM (MROM),a programmable ROM (PROM), an erasable programmable ROM (EPROM), anelectrically erasable programmable ROM (EEPROM), a compact disk ROM(CD-ROM), and a digital versatile disk ROM, etc. In some embodiments,the storage 220 may store one or more programs and/or instructions toperform exemplary methods described in the present disclosure.

The I/O 230 may input and/or output signals, data, information, etc. Insome embodiments, the I/O 230 may enable a user interaction with theprocessing engine 112. In some embodiments, the I/O 230 may include aninput component and an output component. Examples of the input componentmay include a keyboard, a mouse, a touch screen, a microphone, or thelike, or a combination thereof. Examples of the output component mayinclude a display device, a loudspeaker, a printer, a projector, or thelike, or a combination thereof. Examples of the display device mayinclude a liquid crystal display (LCD), a light-emitting diode(LED)-based display, a flat panel display, a curved screen, a televisiondevice, a cathode ray tube (CRT), a touch screen, or the like, or acombination thereof.

The communication port 240 may be connected to a network (e.g., thenetwork 150) to facilitate data communications. The communication port240 may establish connections between the processing engine 112 and theserver 110, the acquisition device 130, the output device 140, and/orthe storage device 120. The connection may be a wired connection, awireless connection, any other communication connection that can enabledata transmission and/or reception, and/or any combination of theseconnections. The wired connection may include, for example, anelectrical cable, an optical cable, a telephone wire, or the like, orany combination thereof. The wireless connection may include, forexample, a Bluetooth™ link, a Wi-Fi™ link, a WiMax™ link, a WLAN link, aZigBee link, a mobile network link (e.g., 3G, 4G, 5G, etc.), or thelike, or a combination thereof. In some embodiments, the communicationport 240 may be and/or include a standardized communication port, suchas RS232, RS485, etc. In some embodiments, the communication port 240may be a specially designed communication port. For example, thecommunication port 240 may be designed in accordance with analog signaltransmission.

FIG. 3 is a block diagram illustrating an exemplary processing engine112 according to some embodiments of the present disclosure. Theprocessing engine 112 may include an acquisition module 310, ageneration module 320, a conversion module 430, and a transmissionmodule 340.

The acquisition module 310 may be configured to obtain informationrelated to the multimedia system 100. For example, the acquisitionmodule 310 may obtain at least two multimedia signals from a pluralityof channels. Each of the at least two multimedia signals may be receivedfrom one of the plurality of channels. The at least two multimediasignals (also be referred to as the multimedia signals for brevity) maybe of the same type or different types of multimedia signals. Forexample, the multimedia signals may include a video signal, an audiosignal, a combined signal of video signal and audio signal, an imagesignal, an animation signal, or the like, or a combination thereof. Moredescriptions regarding the multimedia signals may be found elsewhere inthe present disclosure (e.g., operation 410 in FIG. 4A and the relevantdescriptions).

The generation module 320 may be configured to generate a compositemultimedia digital signal based on the multimedia signals obtained bythe acquisition module 310. In some embodiments, the generation module320 may generate the composite multimedia digital signal by coding themultimedia signals in a frame format. The frame format may include anactive zone and a blanking zone. The active zone may be used to encodeat least part of the multimedia signals. The blanking zone may be usedto encode format information. More descriptions regarding the generationof the composite multimedia digital signal may be found elsewhere in thepresent disclosure (e.g., operation 420 in FIG. 4A, FIG. 4B and therelevant descriptions thereof).

The conversion module 330 may be configured to convert at least part ofthe encoded multimedia signals in the active zone of the compositemultimedia digital signal into analog signals. The converted compositemultimedia digital signal may be a mixed signal of digital signals andanalog signals, and be referred to as a composite multimedia signal.More descriptions regarding the conversion of the composite multimediadigital signal may be found elsewhere in the present disclosure (e.g.,operation 430 in FIG. 4A and the relevant descriptions thereof).

The transmission module 340 may be configured to transmit the compositemultimedia signal to a receiving device via a transmission medium. Thetransmission medium may include any transmission medium that cantransmit analog signals and digital signals, such as a coaxial cable, atwisted pair cable, an optical fiber, or the like, or any combinationthereof. More descriptions regarding the transmission of the compositemultimedia signal may be found elsewhere in the present disclosure(e.g., operation 440 in FIG. 4A and the relevant descriptions thereof).

It should be noted that the above descriptions of the processing engine112 are merely provided for the purposes of illustration, and notintended to limit the scope of the present disclosure. For personshaving ordinary skills in the art, various modifications and changes inthe forms and details of the application of the above method and systemmay occur without departing from the principles of the presentdisclosure. For example, the generation module 320 and the conversionmodule 330 may be integrated into a module configured to generate thecomposite multimedia signal based on the multimedia signals. However,those variations and modifications also fall within the scope of thepresent disclosure.

FIG. 4A is a flowchart illustrating an exemplary process 400A forgenerating and transmitting a composite multimedia signal according tosome embodiments of the present disclosure. In some embodiments, one ormore operations in the process 400A may be implemented in the multimediasystem 100 illustrated in FIG. 1. In some embodiments, one or moreoperations in the process 400A may be stored in a storage device (e.g.,the storage device 120, the storage 220) as a form of instructions, andinvoked and/or executed by the server 110 (e.g., the processing engine112 of the server 110, or the processor 210 of the computing device200).

In 410, the acquisition module 310 may receive at least two multimediasignals from a plurality of channels. Each of the at least twomultimedia signals may be received from one of the plurality ofchannels.

The at least two multimedia signals (also be referred to as themultimedia signals for brevity) may be of the same type or differenttypes of multimedia signals. For example, the multimedia signals mayinclude a video signal, an audio signal, a combined signal of videosignal and audio signal, an image signal, an animation signal, or thelike, or a combination thereof. In some embodiments, each of themultimedia signals may include a video signal and/or an audio signal. Insome embodiments, the multimedia signals may be of any signal form, suchas a digital signal, an analog signal, or a combined signal of digitalsignal and analog signal. Different multimedia signals may be of thesame signal form or different signal forms.

In some embodiments, a channel may correspond to an acquisition device130 or an acquisition component of the acquisition device 130 from whicha multimedia signal is received. For example, the multimedia signals maybe received from different acquisition devices 130 (e.g., differentsurveillance cameras with different monitor areas). As another example,two or more of the multimedia signals may be received from differentacquisition components of one acquisition device 130 (e.g., differentcameras of a multi-view camera). As used herein, if two multimediasignals are received from two acquisition components of an acquisitiondevice 130, the two multimedia signals may be regarded as being receivedfrom two channels.

In some embodiments, at least one of the multimedia signals may includea video signal. The video signal may be received from an acquisitiondevice 130 that include a video signal acquisition unit. In someembodiments, at least one of the multimedia signals may include an audiosignal. The audio signal may be received from an acquisition device 130that includes an audio signal acquisition unit.

In 420, the generation module 320 may generate a composite multimediadigital signal by coding the at least two multimedia signals in a frameformat.

The composite multimedia digital signal in the frame format may includeone or more frames. The frame format of a frame may include an activezone and a blanking zone. The active zone may be used to encode at leastpart of the multimedia signals. The active zones of different frames mayencode the same multimedia signal(s) or different multimedia signals.For illustration purposes, an active zone that encodes all themultimedia signals obtained in operation 410 is described as an example.It should be noted that the embodiments of the present disclosure, withminor modifications known by a person skilled in the art, can be appliedto an active zone that encodes a portion of the multimedia signalsobtained in operation 410. The blanking zone may be used to encodeformat information. In some embodiments, the format information may berelated to the format of the frame, the active zone, and/or the blankingzone. Details regarding the frame format of a frame may be foundelsewhere in the present disclosure (e.g., FIG. 4B and the relevantdescriptions thereof).

The composite multimedia digital signal may be a digital signal. In someembodiments, the multimedia signals received in operation 410 may all bedigital signals. The composite multimedia digital signal may be directlygenerated by coding the digital signals of the multimedia signals.Alternatively, a portion or all of the multimedia signals received inoperation 410 may be analog signal(s). The generation module 320 mayfirst convert the analog signal(s) into digital signal(s), and thengenerate the composite multimedia digital signal by coding the convertedmultimedia signal(s) and the original digital multimedia signal(s) (ifany).

In 430, the conversion module 330 may convert at least part of theencoded multimedia signals in the active zone of the compositemultimedia digital signal into analog signals. The converted compositemultimedia digital signal may be a mixed signal of digital signals andanalog signals, and be referred to as a composite multimedia signal.

In some embodiments, one or more of the multimedia signals may include avideo signal, the conversion module 330 may convert the portion of thecomposite multimedia digital signal which corresponds to the videosignal(s) into analog signals. In some embodiments, one or more of themultimedia signals may include a video signal and an audio signal, theconversion module 330 may convert the portion of the compositemultimedia digital signal which corresponds to the video signal(s) andthe audio signal(s) into analog signal. For brevity, the portion of thecomposite multimedia digital signal which corresponds to the video/audiosignal may be referred to as the video/audio signal. In someembodiments, the conversion module 330 may instruct a digital-to-analogconverter (DAC) or any other device for digital-analog conversion toperform the digital-analog conversion.

Compared with the composite multimedia digital signal, the compositemultimedia signal may be more suitable for long-distance (e.g., longerthan a predetermined distance) transmission. Typically, the transmissiondistance of a transmission medium for digital signals, such as a videographics array (VGA) cable or a network cable may be equal to or smallerthan 100 meters. A digital signal may need to be compressed forlong-distance transmission, which may result in a transmission delay.The transmission distance of a transmission medium for analog signalsmay be about 300 meters, or even about 500 meters.

In some embodiments, the format information encoded in the blanking zoneand/or audio signal(s) in the active zone may not be converted intoanalog signals. The format information and/or the audio signal(s) mayhave a much smaller size than the video signal(s) in the active zone.For example, the size of the blanking zone for encoding the formatinformation may be smaller than 10 bytes. The size of the audiosignal(s) may be 8 bytes or 16 bytes. The small sized format informationand/or audio signals, even being of digital signals, can be transmittedfor a long distance at a low transmission speed. The low transmissionspeed may refer to a transmission speed smaller than a threshold speed(e.g., 9600 bps, 1 kps, 1.17 kps, or 10 kps).

In 440, the transmission module 340 may transmit the compositemultimedia signal to a receiving device via a transmission medium.

The transmission medium may include any transmission medium that cantransmit analog signals and digital signals, such as a coaxial cable, atwisted pair cable, an optical fiber, or the like, or any combinationthereof.

In order to ensure the transmission of the composite multimedia signal,the maximum transmission bandwidth supported by the transmission mediummay be equal to or greater than a required transmission bandwidth of thecomposite multimedia signal. For example, if the composite multimediasignal is generated based on two multimedia signals each of whichrequires a transmission bandwidth bw_s for transmission, the maximumtransmission bandwidth supported by the transmission medium may have tobe equal to or greater than 2*bw_s.

In some embodiments, after the receiving device receives the compositemultimedia signal, the analog signals of the composite multimedia signalmay be converted into digital signals. The conversion may be implementedby an analog-to digital-converter (ADC) or any other device foranalog-to-digital conversion. In some embodiments, the convertedcomposite multimedia signal may be same as or substantially similar tothe composite multimedia digital signal as described in connection withoperation 420. In some embodiments, the receiving device may furtherdemodulate the converted composite multimedia signal, and transmit thedemodulated signal to one or more output devices. Details regarding theprocessing of the composite multimedia signal may be found elsewhere inthe present disclosure (e.g., FIG. 6 and the relevant descriptionsthereof).

It should be noted that the above description regarding the process 400Ais merely provided for the purposes of illustration, and not intended tolimit the scope of the present disclosure. For persons having ordinaryskills in the art, multiple variations and modifications may be madeunder the teachings of the present disclosure. However, those variationsand modifications do not depart from the scope of the presentdisclosure. In some embodiments, one or more other optional operationsmay be added in the process 400A or one or more operations in theprocess 400A may be omitted.

In some embodiment, the multimedia signals received in 410 may includevalid data (e.g., video signals and/or audio signals) as well as otherdata (e.g., blanking zones, blanking lines). The processing engine 112may extract the valid data from multimedia signals and then generate thecomposite multimedia digital signal based on the valid data. In someembodiments, each of the multimedia signals may include one or morehorizontal synchronization signals and/or one or more framesynchronization signals. A horizontal synchronization signal mayindicate a start of an active line. A frame synchronization signal mayindicate a start of a frame. In some embodiments, before encoding themultimedia signals, the processing engine 112 may detect the horizontalsynchronization signal(s) and/or the frame synchronization signal(s) ineach multimedia signal. The processing engine 112 may then extract validdata from the multimedia signals based on the detected horizontalsynchronization signal and/or frame synchronization signal in eachmultimedia signal. For example, the valid data may include data (e.g.,audio signals and/or video signals) encoded between two adjacenthorizontal synchronization signals or two adjacent frame synchronizationsignals. The processing engine 112 may further generate the compositemultimedia digital signal by coding the valid data in the frame formatas described in connection with operation 420. The coding of the validdata may be similar to that of multimedia signals, and the descriptionsthereof are not repeated here.

In some embodiments, the multimedia signals received in operation 410may include one or more modulated multimedia signals and/or one or moreunmodulated multimedia signals. In operation 420, the generation module320 may directly generate the composite multimedia digital signal bycoding the one or more modulated multimedia signals and/or one or moreunmodulated multimedia signals. Alternatively, in operation 420, thegeneration module 320 may modulate the unmodulated multimedia signal(s),and generate the composite multimedia signal based on the modulatedmultimedia signal(s) and the original modulated multimedia signal(s) (ifany).

In some embodiments, the conversion module 330 may compress a portion orall of the composite multimedia signal before transmitting the compositemultimedia signal to the receiving device. For example, the conversionmodule 330 may compressed audio signals in the composite multimediasignal according to various audio compressing techniques. As anotherexample, the conversion module 330 may compressed video signals in thecomposite multimedia signal according to various video compressingtechniques. The receiving device may decompress the compressed portionin the composite multimedia signal after receiving the compositemultimedia signal.

FIG. 4B is a schematic diagram illustrating an exemplary frame format ofa frame 400B of a composite multimedia digital signal according to someembodiments of the present disclosure. The composite multimedia digitalsignal may be generated based on a plurality of multimedia signalsreceived from a plurality of channels by performing operations 410 and420 as described in connection with FIG. 4A.

As shown in FIG. 4B, the frame format of the frame 400B may include anactive zone 450 and a blanking zone 460. The active zone 450 may be usedto encode at least part of the multimedia signals based on which thecomposite multimedia digital signal is generated. The blanking zone 460may be used to encode format information. In some embodiments, theformat information may be related to the format of the frame 400B, theactive zone 450, and/or the blanking zone 460. The format informationrelated to the format of the frame may include the duration of theframe, the size of the frame, or the like. The format informationrelated to the format of the active zone may include the duration of theactive zone, the size of the active zone, the number of active lines inthe active zone, the number of horizontal blanking zones in the activezone, the coding form of the multimedia signals in the active zone, orthe like, or any combination thereof. In some embodiments, the formatinformation may be encoded at any position of the blanking zone 460.Merely by way of example, as shown in FIG. 4B, the format informationmay be encoded in a portion of the blanking zone 460 (e.g., two blankinglines of the blanking zone 460) adjacent to the active zone 450. In someembodiments, the size of the blanking zone 460 may be equal to orsmaller than a threshold size. The threshold size may have any positivevalue, such as 6 bytes, 8 bytes, 10 bytes, 20 bytes, 100 bytes, or thelike. In some embodiments, the threshold size may be 10 bytes.

The active zone 450 may include a plurality of active lines 470 (e.g.,active lines 470A to 470N). The number of the active lines 470 may beany positive value. The number of the active lines 470 may be a presetparameter or be adjusted according to different application scenarios.In some embodiments, the number of the active lines 470 may bedetermined based on the size of the composite multimedia digital signal.The size of the composite multimedia digital signal may be related to,for example, the resolution of the video signals that form the compositemultimedia digital signal. For example, if the composite multimediadigital signal is generated based on four 720p video signals whoseresolutions are all 1280*720, the resolution of the composite multimediadigital signal may be 2560*1440. In that case, the number of activelines 470 may be equal to or greater than 1440.

In some embodiments, at least one of the multimedia signals may includea video signal. The video signal may be encoded in one or more of theactive lines 470. In some embodiments, two or more of the multimediasignals may include a video signal. The video signals may form one ormore combinations of video signals each of which is encoded in one ormore active lines 470. For brevity, a combination of video signals maybe referred to as a video combination. The video combination encoded indifferent active lines 470 may be the same or different. For example, asillustrated in FIG. 4B, video signals 1, 2, 3, and 4 are encoded in theactive zone 450. A combination of the video signals 1 and 2 is encodedin the active line 470A. A combination of the video signals 3 and 4 isencoded in both the active line 470B and the active line 470N. It shouldbe noted that the example illustrated in FIG. 4B is merely provided forillustration purposes. The video signals 1 to 4 may be encoded in theactive lines 470 in any combination form. In some embodiments, an activelines 470 may only encode one of the video signals 1 to 4.

In some embodiments, a separator 475 may be inserted in an active line470 between a pair of adjacent video signals to distinguish the twoadjacent video signals. For example, as illustrated in FIG. 4B, theseparator 475 may be inserted between the video signals 1 and 2 in theactive line 470A. In some embodiments, to generate the compositemultimedia digital signal in the frame format, the processing engine 112(e.g., the generation module 320) may encode the video signals into theactive lines 470 according to the format information in the blankingzone 460. Then the processing engine 112 may inserting one or moreseparators 475 between one or more pair of adjacent video signals in atleast one active line 470.

The active zone 450 may also include one or more horizontal blankingzones 480. Each of the horizontal blanking zone(s) 480 may be locatedbetween a pair of adjacent active lines 470. In some embodiments, theactive zone 450 may include a horizontal blanking zone 480 between eachpair of active lines 470. Optionally, the active zone 450 may furtherinclude an extra horizontal blanking zone 480 corresponding to the firstactive line 470 or the last active line 470. In that case, the number ofthe active lines 470 may be equal to that of the horizontal blankingzones 480. Each active line 470 may have a corresponding horizontalblanking zone 480 that is adjacent to it.

In some embodiments, each of the horizontal blanking zone(s) 480 mayinclude a horizontal synchronization signal 485 configured to indicatethe start of an active line 470. In order to distinguish the separator475 and the horizontal synchronization signal 485, the separator 475 andthe horizontal synchronization signal 485 may be assigned with differenttime widths. Merely by way of example, the time width of the separator475 may be equal to the half of the time width of the horizontalsynchronization signal 485.

In some embodiments, one or more of the multimedia signals may includean audio signal. In the generation of the composite multimedia digitalsignal, the processing engine 112 may encode the audio signal(s) intoone or more horizontal blanking zones 480. Different horizontal blankingzones 480 may encode the same audio signal(s) or different audiosignals. In some embodiments, the audio signal(s) may be encoded intoall or a portion of the horizontal blanking zone(s) 480 of the frame400B. In some embodiments, each audio signal of the multimedia signalsmay be encoded in one horizontal blanking zone 480, respectively. Forexample, if the number of the audio signal(s) is M, M active lines 470and their corresponding horizontal blanking zones 480 may be designatedas a cycle. Each horizontal blanking zone 480 in the cycle may encode anaudio single of the M audio signal(s). Different horizontal blankingzones 480 in the cycle may encode different audio signals.

In some embodiments, each of the multimedia signals may include a videosignal and a corresponding audio signal. The video signals may form oneor more video combinations each of which is encoded in one or moreactive lines 470. The audio signals may also form one or morecombinations of audio signals each of which is encoded in one or morehorizontal blanking zones 480. For brevity, a combination of audiosignals may be referred to as an audio combination. In some embodiments,the audio combination(s) may be formed according to the videocombination(s). Merely by way of example, for an active line 470, theprocessing engine 112 may determine an audio combination according tothe video combination in the active line 470. The audio combination mayinclude audio signals that correspond to the video signals in the videocombination. The processing engine 112 may then encode the audiocombination into the horizontal blanking zone 480 corresponding to theactive line 470. Take the combination of video signals 1 and 2 in theactive lines 470A as an example, the processing engine 112 may determinean audio combination corresponding to the combination of video signal 1and 2. The audio combination may include an audio signal correspondingto the video signal 1 and an audio signal corresponding to the videosignal 2. The audio combination may be encoded into a horizontalblanking zone 480 corresponding to the active line 470A (e.g., thehorizontal blanking zone 480 between the active lines 470A and 470B).

In some embodiments, the size of a horizontal blanking zone 480 may varydepending on the amount of audio signals encoded in the horizontalblanking zone 480. For example, a horizontal blanking zone 480 encodingfewer audio signals may have a relative smaller size than that encodingmore audio signals. As another example, if the video signals in anactive line A have more corresponding audio signals than that of anactive line B, the horizontal blanking zone 480 corresponding the activeline A may have a relative larger size than the horizontal blanking zone480 corresponding to the active line B. As such, the horizontal blankingzone(s) 480 may satisfy the loading requirement of audio signals, and atthe same time, the bandwidth utilization may be increased.

In some embodiments, the format of the active zone 450 may be indicatedand/or prescribed by the format information encoded in the blanking zone460. For example, two or more of the multimedia signals may include avideo signal. The format information in the blanking zone 460 mayindicate a combination form of the video signals in the active lines470. The combination form may include a combination of the video signalsencoded in each active line 470. As another example, two or more of themultimedia signal may include an audio signal. The format information inthe blanking zone 460 may indicate a combination form of the audiosignals in one or more horizontal blanking zones 480. For illustrationpurposes, an example of format information regarding the active zone 450encoded in the blanking zone 460 is illustrated in Table. 1 below:

TABLE 1 An example of format information regarding the active zone 450Header M ID-0 ID-1 SPR ID-3 ID-4 . . . SPR ID-(M-1) ID-M CRCwhere “Header” refers to a code header; “M” denotes the total number ofthe video signals; “ID-0”, “ID-1”, . . . , and “ID-M” respectivelyrefers to a video signal; “CRC” refers to a cyclic redundancy checkcode; and “SPR” refers a separator between two adjacent active lines 470configured to distinguish the adjacent active lines 470. For example,Table. 1 shows that a combination of video signals ID-0 and ID-1, acombination of video signal ID-3 and ID-4, and a combination of videosignals ID-(M−1) and ID-M are encoded in an active line 470,respectively. In some embodiments, the “SPR” may include a horizontalsynchronization signal 485.

It should be noted that the above description of the frame 400B of thecomposite multimedia signal is merely provided for the purposes ofillustration, and not intended to limit the scope of the presentdisclosure. For persons having ordinary skills in the art, multiplevariations and modifications may be made under the teachings of thepresent disclosure. However, those variations and modifications do notdepart from the scope of the present disclosure. In some embodiments,the active zone 470 may encode any type of multimedia signals other thanvideo signals and audio signals, such as an image signal, an animationsignal, or the like, or any combination thereof. In some embodiments,the multimedia signals may be encoded in the active line 470 in anycombination form.

In some embodiments, key information contained in or related to themultimedia signals may be detected, and the frame format of thecomposite multimedia digital signal generated based on the multimediasignals may be adjusted upon the detection of the key information. Thekey information may include any object (e.g., a human, a human face, avehicle, smoke, fire) and/or event (e.g., a motion of human) that a usermay be interested in. The key information may be detected by theacquisition device(s) 130 of the multimedia signals and/or theprocessing engine 112 by analyzing the multimedia signals. Additionallyor alternatively, the key information may be detected by anothercomponent of the multimedia system 100, such as a smoke detector, athermometer, and/or a flame detector installed near or in theacquisition device(s) 130. In some embodiments, the generation module320 may insert a signal (e.g., an alarm signal) corresponding to the keyinformation in the composite multimedia digital signal to indicate theexistence of the key information. For example, the signal correspondingto the key information may be inserted into a blanking zone 460 or ahorizontal blanking zone 480 of a frame in which the key information isincluded. In some embodiments, the processing engine 112 may adjust thesizes of different frames or the resolutions of different multimediasignals in the composite multimedia digital signal in response to thedetection of the key information. Merely by way of example, if a certainmultimedia signal is determined to contain key information in a certainframe, the frame that encodes the certain multimedia signal may beadjusted to have a larger size to support a higher resolution for themultimedia signal.

FIG. 5 is a block diagram illustrating an exemplary receiving device 500according to some embodiments of the present disclosure. The receivingdevice 500 may include a receiving module 510, a conversion module 520,a demodulation module 530, and a transmission module 540.

The receiving module 510 may be configured to receive informationrelated to the multimedia system 100. For example, the receiving module510 may receive a composite multimedia signal in a frame format. Thecomposite multimedia signal be generated based on at least twomultimedia signals received from a plurality of channels. The frameformat may include an active zone and a blanking zone. The active zonemay be configured to encode analog signals, which are converted from atleast part of the multimedia signals. The blanking zone may beconfigured to encode format information. Details regarding the compositemultimedia signal may be found elsewhere in the present disclosure(e.g., operation 430 in FIG. 4, operation 610 in FIG. 6 and the relevantdescriptions thereof).

The conversion module 520 may be configured to convert the analogsignals in the active zone of the composite multimedia signal intodigital signals. The converted composite multimedia signal may be adigital signal and referred to as a composite multimedia digital signal.In some embodiments, the conversion module 520 may instruct ananalog-to-digital converter (ADC) or any other device foranalog-to-digital conversion to perform the analog-to-digitalconversion.

The demodulation module 530 may be configured to demodulate thecomposite multimedia digital signal according to the format informationencoded in the blanking zone. In the demodulation, the demodulationmodule 530 may extract valid information (i.e., the demodulatedcomposite multimedia digital signal) from a carrier wave. Additionallyor alternatively, the demodulation module 530 may determine thestructure and components of the demodulated composite multimedia digitalsignal according to the format information. For example, thedemodulation module 530 may extract the multimedia signals encoded inthe composite multimedia digital signal according to the formatinformation. Details regarding the demodulation of the compositemultimedia digital signal may be found elsewhere in the presentdisclosure (e.g., operation 630 in FIG. 6 and the relevant descriptionsthereof).

The transmission module 540 may be configured to transmit thedemodulated composite multimedia digital signal. For example, thetransmission module 540 may transmit the demodulated compositemultimedia digital signal to one or more output devices 140. In someembodiments, the demodulation module 530 may extract the multimediasignals encoded in the composite multimedia digital signal, and thetransmission module 540 may transmit each multimedia signal to adistinctive output device 140. In some embodiments, the transmissionmodule 540 may transmit two or more of the multimedia signals to thesame output device 140.

It should be noted that the above descriptions of the receiving device500 are merely provided for the purposes of illustration, and notintended to limit the scope of the present disclosure. For personshaving ordinary skills in the art, various modifications and changes inthe forms and details of the application of the above method and systemmay occur without departing from the principles of the presentdisclosure. For example, the conversion module 520 and the demodulationmodule 530 may be integrated into a module to convert and demodulate thecomposite multimedia signal. However, those variations and modificationsalso fall within the scope of the present disclosure.

FIG. 6 is a flowchart illustrating an exemplary process 600 forprocessing a composite multimedia signal according to some embodimentsof the present disclosure. In some embodiments, one or more operationsin the process 600 may be implemented in the multimedia system 100illustrated in FIG. 1. In some embodiments, one or more operations inthe process 600 may be stored in a storage device (e.g., the storagedevice 120, the storage 220) as a form of instructions, and invokedand/or executed by the server 110 (e.g., the processing engine 112 ofthe server 110, or the processor 210 of the computing device 200) or areceiving device 500 of the composite multimedia signal. Forillustration purposes, an implementation of the process 600 on thereceiving device 500 is described as an example.

In 610, the receiving module 510 may receive a composite multimediasignal in a frame format.

In some embodiments, the composite multimedia signal may be generatedbased on at least two multimedia signals received from a plurality ofchannels. The at least two multimedia signals may also be referred to asmultimedia signals for brevity. The multimedia signals may include avideo signal, an audio signal, a text signal, an image signal, or thelike, or any combination thereof. In some embodiments, a channel maycorrespond to an acquisition device an acquisition component of theacquisition device 130 from which a multimedia signal is received. Themultimedia signals may be substantially similar to the multimediasignals described in connection with operation 410, and the descriptionsthereof are not repeated here.

The composite multimedia signal in the frame format may include one ormore frames. The frame format of a frame may include an active zone anda blanking zone. The blanking zone may be configured to encode formatinformation. The format information may include format informationrelated to the format of the frame, the active zone, and/or the blankingzone. In some embodiments, a portion or all of the multimedia signalsmay be converted into analog signals in the generation of the compositemultimedia signal. The active zone may be configured to encode theanalog signals converted from the portion or all of the multimediasignals. Optionally, a portion of the multimedia signals may not beconverted into analog signals in the generation of the compositemultimedia signal. The active zone may be further configured to encodethe unconverted part of the multimedia signals. For example, each of themultimedia signals may include a video signal and an audio signal. Thevideo signals may be converted into analog signals. The audio signalsand the analog signals converted from the video signals may be encodedin the active zone. In some embodiments, the composite multimedia signalmay be generated based on the multimedia signals by performingoperations 410 to 430 as described in connection with FIG. 4.

In 620, the conversion module 520 may convert the analog signals in theactive zone into digital signals. The converted composite multimediasignal may be a digital signal and referred to as a composite multimediadigital signal. The format of the composite multimedia digital signalmay be similar to that described in operation 420, and the descriptionsthereof are not repeated. In some embodiments, the conversion module 520may instruct an analog-to-digital converter (ADC) or any other devicefor analog-to-digital conversion to perform the analog-to-digitalconversion.

In 630, the demodulation module 530 may demodulate the compositemultimedia digital signal according to the format information encoded inthe blanking zone. In the demodulation, the demodulation module 530 mayextract valid information (i.e., the demodulated composite multimediadigital signal) from a carrier wave.

In some embodiments, the demodulation module 530 may determine thestructure and components of the demodulated composite multimedia digitalsignal according to the format information. For example, as described inconnection with FIG. 4B, the format information may indicate acombination form of video signals in the active lines of the activezone. The demodulation module 530 may determine the video signalsencoded in the active lines based on the format information. Optionally,the demodulation module 530 may further extract the video signals in anactive line according to the separator(s) between one or more pair ofadjacent video signals in the active line. As another example, theformat information may indicate a coding form of audio signals in thehorizontal blanking zone(s) of the active zone. The demodulation module530 may determine and extract the audio signals based on the formatinformation.

In some embodiments, the demodulation module 530 may determine one ormore parameters related to the multimedia signals, such as thebrightness, the chromaticity, or the like in the signal demodulation.

In 640, the transmission module 540 may transmit the demodulatedcomposite multimedia digital signal to one or more output devices 140.

Exemplary output device 140 may include a mobile device 140-1, acomputer 140-2, a display device 140-3, a loudspeaker 140-4, a headset,a microphone, a music player, an e-book reader, a printer, a projector,or the like, or a combination thereof. In some embodiments, thedemodulation module 530 may extract the multimedia signals in thedemodulated composite multimedia digital signal as described inconnection with operation 630. The transmission module 540 may transmiteach multimedia signal to a suitable output device 140. For example, thetransmission module 540 may transmit an audio signal to an audio outputdevice. In some embodiments, the transmission module 540 may transmiteach multimedia signal to a distinctive output device 140. In someembodiments, the transmission module 540 may transmit two or more of themultimedia signals to a same output device 140.

It should be noted that the above description regarding the process 600is merely provided for the purposes of illustration, and not intended tolimit the scope of the present disclosure. For persons having ordinaryskills in the art, multiple variations and modifications may be madeunder the teachings of the present disclosure. However, those variationsand modifications do not depart from the scope of the presentdisclosure. For example, the receiving device may include one or moreoutput components. Additionally or alternatively, the output device(s)140 may be integrated into the receiving device, for example, as one ormore output components. The receiving device may process the compositemultimedia signal to extract the multimedia signals, and output at leastpart of the multimedia signals by itself.

In some embodiments, the receiving device may transmit a control signalto one or more acquisition devices that acquire the multimedia signals.The control signal may control the acquisition device(s) to perform acertain action, for example, to take a picture, rotate, or stopoperating. In some embodiments, when receiving the composite multimediasignal, the receiving device may determine whether currently receiveddata is encoded in the blanking zone of the composite multimedia signal.Upon a determination that the currently received data is encoded in theblanking zone, the receiving device may transmit the control signal tothe one or more acquisition device(s). More Descriptions regarding thetransmission of the control signal to the acquisition device(s) may befound in, for example, International Application No. PCT/CN2018/111361,entitled “SYSTEMS AND METHODS FOR MULTIMEDIA SIGNAL PROCESSING ANDTRANSMISSION,” filed on even date, the contents of which are herebyincorporated by reference.

FIGS. 7 and 8 are schematic diagrams illustrating exemplary traditionalways of transmitting video signals.

In the field of video surveillance, a video signal (e.g., an analogyvideo signal) is typically transmitted through a transmission mediumwith a transmission bandwidth of 2 k. When transmitting a plurality ofvideo signals acquired from a plurality channels, each video signal mayneed a transmission medium with 2 k transmission bandwidth, which mayresult in a waste of transmission recourses. For example, as illustratedin FIG. 7, a 720p video signal may only use a portion of the total 2 ktransmission bandwidth, leaving the rest of the transmission bandwidthunused. As another example, as shown in FIG. 8, each of the videosignals acquired by the plurality of acquisition devices (e.g.,acquisition devices 130A, 130B, 130C, and 130D) may be transmitted to areceiving device via a single transmission medium (e.g., a cable),respectively. As yet another example, a single channel video signal maybe generated by stitching the video signals. The single channel videosignal may then be compressed into bit streams using a video compressiontechnique such as H.264. The bit streams may be sent to the receivingdevice via a wireless network. The receiving device may decompress thebit streams and process the decompressed bit streams, and furthertransmit the decompressed bit streams to an output device 140 (e.g., adisplay) for display. The compression of the single channel video signalmay take time and reduce the video quality.

FIGS. 9 and 10 are schematic diagrams illustrating exemplary ways oftransmitting video signals according to some embodiments of the presentdisclosure.

When transmitting a plurality of video signals acquired from a pluralitychannels, a composite video signal or a composite digital video signal(collectively referred to as a composite video signal hereinafter) maybe generated based on the plurality of video signals. In someembodiments, the composite video signal may be generated by performingthe methods for generating a composite multimedia signal disclosed inthe present disclosure (e.g., the process 400A). The composite videosignal may be transmitted via a single transmission medium. For example,as shown in FIG. 9, a transmission medium with 2 k transmissionbandwidth may be used to transmit a composite video signal generatedbased on four 720p video signals. The transmission bandwidth of thetransmission medium may be fully used. As another example, as shown inFIG. 10, the video signals acquired by the plurality of acquisitiondevices (e.g., acquisition devices 130A, 130B, 130C, and 130D) may betransmitted to a processing device (e.g., the processing engine 112) forprocessing. The processing device may generate a composite video signalby coding the video signals. The composite video signal may betransmitted to a receiving device via a single cable.

Compared with the traditional ways of transmitting video signals asdescribed in connection with FIGS. 7 and 8, the ways of transmittingvideo signals disclosed in the present discourse may improve thetransmission efficiency and reduce the transmission cost. In addition,the video signals may not need to be compressed or transmitted via awireless network, which may ensure the video quality, the synchronoustransmission, and the real-time transmission.

FIG. 11 is a schematic diagram illustrating an exemplary process ofgenerating a composite video signal 1100 according to some embodimentsof the present disclosure.

The composite video signal 1100 may be generated based on four 720pvideo signals (denoted as video signal 1, 2, 3, and 4) acquired fromfour channels. Each video signal may include 750 lines per frame and1600 sample periods (e.g., luma sample periods) in each line. The videosignal may include an active zone 1110 and a blanking zone 1120. Theactive zone 1110 may include 720 active lines and 1280 samples (e.g.,luma samples or RGB samples) in each active line.

In some embodiments, the composite video signal 1100 may be generated bycoding the video signals in a frame format by performing the methods forgenerating a composite multimedia signal disclosed in the presentdisclosure (e.g., the process 400A). The composite video signal 1100 mayinclude 1500 total lines per frame and 3200 sample periods (e.g., lumasample periods) in each line. The composite video signal 1100 mayinclude an active zone 1130 and a blanking zone 1140. The active zonemay include 1440 active lines and 2560 samples (e.g., luma samples orRGB samples) in each active line. The video signals 1 to 4 may becombined into one or more video combinations, which may be encoded inone or more active lines of the active zone 1130. For example, asillustrated in FIG. 11, a combination of the video signals 1 and 2 maybe encoded in the first, third, fifth, seventh, and ninth active lines.A combination of the video signals 3 and 4 may be encoded in the second,fourth, sixth, eighth, and tenth active lines. The blanking zone 1140may be similar to the blanking zone 460 as described in connection withFIG. 4B, and the descriptions thereof are not repeated.

Having thus described the basic concepts, it may be rather apparent tothose skilled in the art after reading this detailed disclosure that theforegoing detailed disclosure is intended to be presented by way ofexample only and is not limiting. Various alterations, improvements, andmodifications may occur and are intended to those skilled in the art,though not expressly stated herein. These alterations, improvements, andmodifications are intended to be suggested by the present disclosure,and are within the spirit and scope of the exemplary embodiments of thepresent disclosure.

Moreover, certain terminology has been used to describe embodiments ofthe present disclosure. For example, the terms “one embodiment,” “anembodiment,” and/or “some embodiments” mean that a particular feature,structure or characteristic described in connection with the embodimentis included in at least one embodiment of the present disclosure.Therefore, it is emphasized and should be appreciated that two or morereferences to “an embodiment,” “one embodiment,” or “an alternativeembodiment” in various portions of this specification are notnecessarily all referring to the same embodiment. Furthermore, theparticular features, structures or characteristics may be combined assuitable in one or more embodiments of the present disclosure.

Further, it will be appreciated by one skilled in the art, aspects ofthe present disclosure may be illustrated and described herein in any ofa number of patentable classes or context including any new and usefulprocess, machine, manufacture, or composition of matter, or any new anduseful improvement thereof. Accordingly, aspects of the presentdisclosure may be implemented entirely hardware, entirely software(including firmware, resident software, micro-code, etc.) or combiningsoftware and hardware implementation that may all generally be referredto herein as a “block,” “module,” “engine,” “unit,” “component,” or“system.” Furthermore, aspects of the present disclosure may take theform of a computer program product embodied in one or more computerreadable media having computer readable program code embodied thereon.

A computer readable signal medium may include a propagated data signalwith computer readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including electro-magnetic, optical, or thelike, or any suitable combination thereof. A computer readable signalmedium may be any computer readable medium that is not a computerreadable storage medium and that may communicate, propagate, ortransport a program for use by or in connection with an instructionexecution system, apparatus, or device. Program code embodied on acomputer readable signal medium may be transmitted using any appropriatemedium, including wireless, wireline, optical fiber cable, RF, or thelike, or any suitable combination of the foregoing.

Computer program code for carrying out operations for aspects of thepresent disclosure may be written in any combination of one or moreprogramming languages, including an object oriented programming languagesuch as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C #, VB.NET, Python or the like, conventional procedural programming languages,such as the “C” programming language, Visual Basic, Fortran 1703, Perl,COBOL 1702, PHP, ABAP, dynamic programming languages such as Python,Ruby and Groovy, or other programming languages. The program code mayexecute entirely on the user's computer, partly on the user's computer,as a stand-alone software package, partly on the user's computer andpartly on a remote computer or entirely on the remote computer orserver. In the latter scenario, the remote computer may be connected tothe user's computer through any type of network, including a local areanetwork (LAN) or a wide area network (WAN), or the connection may bemade to an external computer (for example, through the Internet using anInternet Service Provider) or in a cloud computing environment oroffered as a service such as a software as a service (SaaS).

Furthermore, the recited order of processing elements or sequences, orthe use of numbers, letters, or other designations therefore, is notintended to limit the claimed processes and methods to any order exceptas may be specified in the claims. Although the above disclosurediscusses through various examples what is currently considered to be avariety of useful embodiments of the disclosure, it is to be understoodthat such detail is solely for that purpose, and that the appendedclaims are not limited to the disclosed embodiments, but, on thecontrary, are intended to cover modifications and equivalentarrangements that are within the spirit and scope of the disclosedembodiments. For example, although the implementation of variouscomponents described above may be embodied in a hardware device, it mayalso be implemented as a software-only solution—e.g., an installation onan existing server or mobile device.

Similarly, it should be appreciated that in the foregoing description ofembodiments of the present disclosure, various features are sometimesgrouped together in a single embodiment, figure, or description thereoffor the purpose of streamlining the disclosure aiding in theunderstanding of one or more of the various embodiments. This method ofdisclosure, however, is not to be interpreted as reflecting an intentionthat the claimed subject matter requires more features than areexpressly recited in each claim. Rather, claimed subject matter may liein less than all features of a single foregoing disclosed embodiment.

What is claimed is:
 1. A method implemented on a computing device havingat least one processor and at least one non-transitory computer-readablestorage medium, comprising: receiving at least two multimedia signalsfrom a plurality of channels, wherein at least one of the at least twomultimedia signals includes a video signal; generating a compositemultimedia digital signal by coding the at least two multimedia signalsin a frame format, the frame format including an active zone and ablanking zone, the active zone being configured to encode at least partof the at least two multimedia signals, and the blanking zone beingconfigured to encode format information, the size of the blanking zoneof the frame format being smaller than 10 bytes; converting at leastpart of the encoded multimedia signals in the active zone into analogsignals to generate a composite multimedia signal; and transmitting thecomposite multimedia signal to a receiving device via a transmissionmedium.
 2. The method of claim 1, wherein the active zone is configuredto encode the video signal, and the converting the at least part of theencoded multimedia signals in the active zone into analog signalsfurther comprises: converting the video signal in the active zone intoanalog signals.
 3. The method of claim 1, wherein the active zone of theframe format includes: a plurality of active lines configured to encodethe video signal, and a horizontal blanking zone between at least onepair of adjacent active lines of the plurality of active lines, thehorizontal blanking zone including a horizontal synchronization signal.4. The method of claim 3, wherein each of the at least two multimediasignals includes a video signal, and the format information indicates acombination form of the video signals in the plurality of active linesin the active zone.
 5. The method of claim 4, wherein the generating thecomposite multimedia digital signal by coding the at least twomultimedia signals in the frame format comprises: encoding the videosignals into the plurality of active lines according to the formatinformation; and inserting a separator between at least one pair ofadjacent video signals in at least one of the plurality of active lines.6. The method of claim 5, wherein the horizontal synchronization signaland the separator have different time widths.
 7. The method of claim 4,wherein: the active zone includes the horizontal blanking zonecorresponding to each of the plurality of active lines, each of the atleast two multimedia signals includes an audio signal, and thegenerating the composite multimedia digital signal further comprises:for each of the plurality of active lines in the active zone,determining a combination of the audio signals according to thecombination form of the video signals in the active line; and encodingthe combination of the audio signals into the horizontal blanking zonecorresponding to the active line.
 8. The method of claim 3, wherein: atleast one of the at least two multimedia signals includes an audiosignal, and the generating the composite multimedia digital signalfurther comprises: encoding the audio signal into the horizontalblanking zone.
 9. The method of claim 1, wherein the method furthercomprises: converting the analog signals of the composite multimediasignal into digital signals.
 10. The method of claim 1, wherein: each ofthe at least two multimedia signals includes at least one of ahorizontal synchronization signal or a frame synchronization signal, andthe generating the composite multimedia digital signal by coding the atleast two multimedia signals further comprises: detecting the at leastone of the horizontal synchronization signal or the framesynchronization signal in each multimedia signal; extracting valid datafrom the at least two multimedia signals based on the detected at leastone of the horizontal synchronization signal or the framesynchronization signal in each multimedia signal; and generating thecomposite multimedia digital signal by coding the valid data.
 11. Amethod implemented on a computing device having at least one processorand at least one non-transitory computer-readable storage medium,comprising: receiving a composite multimedia signal in a frame format,the composite multimedia signal being generated based on at least twomultimedia signals that are received from a plurality of channels,wherein at least one of the at least two multimedia signals includes avideo signal, the frame format includes an active zone and a blankingzone, the active zone is configured to encode analog signals convertedfrom at least part of the at least two multimedia signals, and theblanking zone is configured to encode format information, the size ofthe blanking zone of the frame format being smaller than 10 bytes;demodulating the composite multimedia signal according to the formatinformation; and transmitting the demodulated composite multimediasignal to one or more output devices, wherein the demodulating thecomposite multimedia signal according to the format informationcomprises: converting the analog signals in the active zone into digitalsignals.
 12. The method of claim 11, wherein the transmitting thedemodulated composite multimedia digital signal to one or more outputdevices further comprises: determining the at least two multimediasignals from the demodulated composite multimedia signal; andtransmitting the at least two multimedia signals to at least two outputdevices, wherein each of the at least two multimedia signals istransmitted to one of the at least two output devices.
 13. A system, fortransmitting a composite multimedia signal, comprising: a non-transitorycomputer-readable storage medium storing a set of instructions; at leastone processor in communication with the non-transitory computer-readablestorage medium, wherein when executing the set of instructions, the atleast one processor is configured to cause the system to: receive atleast two multimedia signals from a plurality of channels, wherein atleast one of the at least two multimedia signals includes a videosignal; generate a composite multimedia digital signal by coding the atleast two multimedia signals in a frame format, the frame formatincluding an active zone and a blanking zone, the active zone beingconfigured to encode at least part of the at least two multimediasignals, and the blanking zone being configured to encode formatinformation, the size of the blanking zone of the frame format beingsmaller than 10 bytes; convert at least part of the encoded multimediasignals in the active zone into analog signals to generate a compositemultimedia signal; and transmit the composite multimedia signal to areceiving device via a transmission medium.
 14. The system of claim 13,wherein the active zone is configured to encode the video signal, and toconvert the at least part of the encoded multimedia signals in theactive zone into analog signals, the at least one processor is furtherconfigured to cause the system to: convert the video signal in theactive zone into analog signals.
 15. The system of claim 13, wherein theactive zone of the frame format includes: a plurality of active linesconfigured to encode the video signal, and a horizontal blanking zonebetween at least one pair of adjacent active lines of the plurality ofactive lines, the horizontal blanking zone including a horizontalsynchronization signal.
 16. The system of claim 15, wherein each of theat least two multimedia signals includes a video signal, and the formatinformation indicates a combination form of the video signals in theplurality of active lines in the active zone.
 17. The system of claim16, wherein to generate the composite multimedia digital signal bycoding the at least two multimedia signals in the frame format, the atleast one processor is further configured to cause the system to: encodethe video signals into the plurality of active lines according to theformat information; and insert a separator between at least one pair ofadjacent video signals in at least one of the plurality of active lines.18. The system of claim 16, wherein: the active zone includes thehorizontal blanking zone corresponding to each of the plurality ofactive lines, each of the at least two multimedia signals includes anaudio signal, and to generate the composite multimedia digital signal,the at least one processor is further configured to cause the system to:for each of the plurality of active lines in the active zone, determinea combination of the audio signals according to the combination form ofthe video signals in the active line; and encode the combination of theaudio signals into the horizontal blanking zone corresponding to theactive line.
 19. The system of claim 15, wherein: at least one of the atleast two multimedia signals includes an audio signal, and to generatethe composite multimedia digital signal, the at least one processor isfurther configured to cause the system to: encode the audio signal intothe horizontal blanking zone.
 20. The method of claim 1, wherein thecomposite multimedia signal is a mixed signal of digital signals and theanalog signals, the digital signals including the format informationencoded in the blanking zone.